Sam published his response to the video on his Tumblr blog and has kindly allowed me to republish it here.

“After watching the Critical Jim episode on my Station 51 map pack for Half-Life 2: Episode Two, I’ve come up with some notes on general rules for single player first person shooter design and areas where I need to improve. Nothing groundbreaking, just helpful to list it all in one place. They did a great job, I don’t disagree with any of the feedback.
A little painful to see all the failings laid out, but I’m glad to see them.

As far as I can tell, there isn’t really an enjoyable part to Station 51, or at least nothing that I added to the default Half-Life 2 combat. Station 51 is a poorly paced slog through mobs of enemies thrown at the player in thinly veiled combat arenas, with no story or any reason to play.

Disappointing that it turned out that way after the time put into it, but that’s how it is. How long it took to make doesn’t matter, only the end result is important. Hopefully it serves as a learning experience for me, and maybe this will help others learn these lessons.”

The biggest issue appears to be pacing. I throw too much at the player without space to breathe, and there aren’t any areas where the player can explore or just look around.

I also don’t have enough of a story or any sort of hook to keep the player interested, it’s just one grinding battle after another. Even story as simple as “Hey, look at that interesting building ahead. Let’s try and get over there!” is missing.

My levels aren’t believable as real spaces. They look like what they are, combat arenas strung together with window dressing. This one is the most difficult to see a solution for. Using more reference might help. Another might be planning out a space as a real world location first, then breaking it up into a gameplay space. But actual real world locations are usually terrible gameplay spaces. But it’s obviously possible to find a happy medium. I really need to work on this one.

Having only perpetual combat is bad. The player needs space to relax and recover. That’s what the puzzles are for in Half-Life 2, at least partially.

The player needs at least enough story that they want to progress and see what’s next. More planning would help with this, but I think I need to work on my storytelling skills in general. In person, I can’t tell a story to save my life, even though I’ve read up on the principles and ideas behind telling a good story. This goes a little deeper, but I’m not sure what story I want to tell in general.

Combat encounters need to be introduced – show the player the space, let them explore it a bit and plan, then introduce enemies.

Don’t spawn enemies until the player is deep within the combat space.

Ranged weapon enemies shouldn’t charge at the player.

Eliminate areas where the player can sit in a safe place – force the player out.

Don’t spawn tons of enemies at once – this gives no time to plan, and players just spray bullets until they’re dead.

Have enemies enter in unique ways to announce their presence to the player, so the battle feels more dynamic.

Spread out enemy spawns, give them to the player a bit at a time.

Two major challenges at once is probably too much – attack chopper and Combine troops, for example, at least in the size of the arena given. Use lower intensity challenges like mines or dumb enemies to keep it exciting without being overwhelming.

It shouldn’t be difficult for player to manoeuvre around critical areas. Jumping and ladders during combat is frustrating.

Getting weapons and abilities should be special, not just laying on the ground to pick up.

Tease the player with it, then have them find their way to it.

Add music, and better audio cues.

Make the way forward glaringly obvious. Lights, action, blinking sign.

In the same vein, the results of a player’s action should be immediate and clear. We’re talking fireworks, strobes, flashing lights, lasers, the works.

Don’t have places where the only way down is to drop and hurt yourself.

Keep supplies and safe spots separate, to keep the player actively moving around the map.

More foreshadowing of enemies and goals – there needs to be a build up, the player has to know about something to care about it, the anticipation and desire is an important part.

Watching NPC factions fight and interact is fun and takes some pressure off the player.

More secrets and rewards for exploration. There were a few small ones dotted in there that weren’t spotted in the playthrough, but more of these would be better. I always enjoy these in games – Quake IV is an example that sticks with me, and of course it’s part of the first person shooter tradition.

“Altogether, a very interesting watch, I look forward to the future Critical Jim episodes!”

I’d like to thank Sam for being so open to the process. If you are a modder and would like you work featured here or if you are a reader and would like to suggest a mod that Jim looks at, please let us know via the Contact page.